Microfused silicon strain gauge (MSG) pressure sensors are widely used throughout a number of industries. In the automotive industry, MSGs are used for applications ranging from brake, transmission, and fuel pressure sensors, to occupant weight force sensing. Such pressure sensors typically include silicon strain gauge elements which are glass-bonded to a stainless steel diaphragm of a steel port body. Wheatstone bridge, or other strain gauge configurations are sometimes employed to yield a linear voltage output which is directly proportional to the applied pressure on the steel diaphragm by calibration.
However, inaccuracies tend to occur in typical MSGs in a number of ways. For example, when temperature rises above 110 Celsius, chemical decomposition tends to occur within the glass generating mobile ions. When the steel port body is grounded, the mobile ions will flock towards the resistors closest to the supply voltage. Disparate ion accumulate across the resistors can lead to sensor signal drift. Further, designs which seek to avoid sensor signal drift can result in sensors with reduced sensitivity, unfavorable resistor or pad positioning, or other inaccuracies.